Improper Check for Unusual or Exceptional Conditions
Noroxi assessment
Priority: Monitor (action score 21/100)
- The sources we track (CISA KEV, Exploit-DB, Metasploit, Nuclei, GitHub) show no public exploit code or exploitation in the wild.
- Probability of exploitation in the next 30 days: 0.55% (FIRST EPSS).
- Anyone who can reach it over the internet can trigger it. No account or password is required. No user action is required. No special conditions are required; it is repeatable.
- According to CISA the attack is automatable: targets can be found by mass scanning.
- Fixed version: ABB AC500 V2 2.8.6.
Low priority for now. Upgrade to ABB AC500 V2 2.8.6 or later.
Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it
Improper Input Validation vulnerability in ABB AC500 V2 PM5xx allows Client-Server Protocol Manipulation.This issue affects AC500 V2: from 2.0.0 before 2.8.6.
- Published
- Mar 31, 2023
- Updated
- Jun 17, 2026
- EPSS
- 0.6% · 45th percentile
- CWE
- CWE-754
Report tools
Action score
21
Monitor
Low priority for now.
- CVSS
- 21 / 40 · 5.3 / 10
- CISA KEV
- 0 / 30 · Not listed
- EPSS
- 0 / 30 · 0.6%
CISA SSVC decision
- Exploitation
- none
- Automatable
- yes
- Technical impact
- partial
Vulnrichment: CISA's decision-tree inputs.
CNA vs NVD score
- NVD
- 5.3
- CNA · ABB
- 5.3
- agree
The score given by the assigning authority versus NVD’s independent score. A gap means the severity is contested.
Get told when this record changes
- Not in KEV: no record of exploitation in the wild
- No public exploit code on record
- A fix has been released
If any of these changes, we'll tell you in the daily email digest.
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Noroxi analysis
What does it mean in your environment?
The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.
We use this product, ask for helpAffected systems
Is your version affected?
Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.
| Vendor | Product | CPE |
|---|---|---|
| abb | ac500 cpu firmware | cpe:2.3:o:abb:ac500_cpu_firmware |
| abb | pm5630-2eth | cpe:2.3:h:abb:pm5630-2eth |
| abb | pm5650-2eth | cpe:2.3:h:abb:pm5650-2eth |
| abb | pm5670-2eth | cpe:2.3:h:abb:pm5670-2eth |
| abb | pm5675-2eth | cpe:2.3:h:abb:pm5675-2eth |
| abb | pm571-eth-v14x | cpe:2.3:h:abb:pm571-eth-v14x |
| abb | pm571-v14x | cpe:2.3:h:abb:pm571-v14x |
| abb | pm572 | cpe:2.3:h:abb:pm572 |
| abb | pm573-eth | cpe:2.3:h:abb:pm573-eth |
| abb | pm581-eth-v14x | cpe:2.3:h:abb:pm581-eth-v14x |
| abb | pm581-v14x | cpe:2.3:h:abb:pm581-v14x |
| abb | pm582 | cpe:2.3:h:abb:pm582 |
and 18 more
Affected versions
NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.
- abb ac500 cpu firmware2.0.0 and later · before 2.8.6
Versions reported by the vendor
Affected version ranges reported by the assigning authority (ABB). Independent of NVD's CPE analysis and usually ahead of it.
ABB AC500 V2
- 2.0.0 and later · before 2.8.6affected · release
Same product
abb: all recordsOther highest-scoring records for the same primary product.
- CVE-2020-24685AC500 V2 unauthenticated crafter packet vulnerability34Monitor
Remediation
Which version to upgrade to
Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.
| Product / package | Fixed version | Source |
|---|---|---|
| ABB AC500 V2 | 2.8.6 | Vendor (CNA) |
Exploit status
No known public exploit
No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.
Research context
For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.
Timeline
From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.
No dated events beyond publication.
FIRST EPSS daily score; only changes of 0.01 or more are recorded (step chart).
Patch and commit links
Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.
No commit or PR link among the references.
Credits
All researchersFinders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.
- the followingfinder
Variant candidates
Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.
No nightly-computed relations.
Chain candidates
An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.
—
Bug bounty scope
The product’s vendor appears in a public program. Matched by name; verify the scope text in the program.
Technical details
Attack conditions
- Anyone who can reach it over the internet can trigger it.
- No account or password is required.
- No user action is required.
- No special conditions are required; it is repeatable.
If successful
- Confidentiality
- none
- Integrity
- none
- Availability
- low · the service can be disrupted
- Attack vector
- Network
- Attack complexity
- Low
- Privileges required
- None
- User interaction
- None
- Scope
- Unchanged
- Confidentiality impact
- None
- Integrity impact
- None
- Availability impact
- Low
Weakness class (CWE)
CWE-754 · Improper Check for Unusual or Exceptional ConditionsCVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
nvd-primary
Attack context
MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.
MITRE has no CAPEC/ATT&CK mapping for this CWE.
Change log
- Fix✗ → ✓
For records you follow, these changes also arrive as notifications. →
References
Vendor advisories and official records. Exploit/PoC links are deliberately left out.